PROJECT SUMMARY: Urban air pollution is a significant public health problem with estimated mortality impacts predominantly among infants and elderly people with pre-existing cardiovascular and respiratory disease. Research on ambient air pollution health effects has begun shifting research objectives away from the single-pollutant paradigm to a more multipollutant or mixtures perspective in order to better understand the impacts of ?real world? air pollution exposures on human health. Another area that is fundamentally linked to air quality and of increasing concern for public health is climate change. During the initial K99 phase, I will work closely with mentors to develop improved statistical methodologies for assessing the effects of multipollutant exposures in epidemiological studies, a natural extension of my current postdoctoral research. I will shift focus from identifying the types of air pollutant mixtures that occur in the environment to characterizing multipollutant exposures for epidemiological research. These will be applied to two ongoing epidemiological investigations that are being conducted within the Southeastern Center for Air Pollution Epidemiology (SCAPE); a US EPA funded Clean Air Research Center (CLARC, R834799) shared between Emory University and Georgia Institute of Technology: a short-term ecological study and a long-term cohort study. During the mentored phase, I will develop multipollutant temporal profiles for the investigation of short-term associations with multipollutant exposure and cardiorespiratory health outcomes. Next, I will develop multipollutant spatial profiles for the investigation of long-term associations between multipollutant exposure and the development of respiratory disease. During this phase, I will also receive new training in biostatistical and epidemiologic methods focused on environmental epidemiology at Emory University. Transitioning to independence in the R00 phase of the award, I will merge these new skills with my PhD training as I pursue research focused on understanding the implications of climate on air quality mixtures. My first independent aim will examine the meteorological sensitivity of specific multipollutant combinations in order to better understand potential changes in air pollutant mixtures under various climate scenarios. The final proposed aim is to develop environmental profiles for the examination of human health vulnerability to heat and multipollutant mixtures. At the conclusion of this award, I will have demonstrated expertise in analyzing effects for the emerging research areas of multipollutant mixtures and climate variability, providing a firm basis for my career as an environmental health scientist focusing on exposure characterizations for epidemiological research.